Fig. 1. Isolated single TA muscle fibres lose cytoplasm and nuclei during ageing. (A-D) Micrographs of DAPI-stained nuclei in fibres. At 2 months (A), all fibres show well-spaced oval peripheral nuclei aligned with the fibre axis. At 26-29 months, some small (B) and large (C) fibres have elongated or mis-orientated nuclei, or nuclear chains (D). Vertical bars denote fibre diameter. Horizontal bar, 100 µm. Mean fibre cross-sectional area (E), nuclei per unit fibre length (F), surface area domain size (SADS, G) and volume domain size (VDS, H) in wild-type mice at 2 months (number of animals per group, n=9), 12 months (n=5), 22-24 months (n=5) and 26-29 months (n=8). **P<0.01. Error bars indicate animal to animal s.e.m.